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Chemistry 2022 Aug 9. Epub 2022 Aug 9.

Center of Biomedical Research, Biological and Synthetic Chemistry, Raebareli Road, SGPGIMS Campus, 226014, India, 226014, Lucknow, INDIA.

Herein, development and detailed investigation of a SN'-type intramolecular aromatic substitution reaction involving α-arylazaoxyallyl cation intermediate, is disclosed. The study showcased that while α-aryl-α-chlorohydroxamate could be activated by a combination of base and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) into the corresponding azaoxyallyl cations, it could further emerge into a π-extended species involving the adjacent α-aryl moiety, and this transition is contingent on electronic effects of the aromatic ring as well as on α-substituents. An effective activation of the α-aromatic ring could pave the path for intramolecular Ar(Csp2)-N bond formation towards oxindoles. Read More

Acc Chem Res 2022 Aug 19;55(15):2123-2137. Epub 2022 Jul 19.

State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong.

ConspectusCatalytic C-N bond cross-coupling reactions have been a subject of fundamental importance in synthetic organic and medicinal chemistry because amides and amines are ubiquitous motifs in natural products, functional materials, and pharmaceuticals. Since the pioneering works of Breslow and Mansuy on the metalloporphyrin-catalyzed direct hydrocarbon amidation using sulfonyliminoiodinane reagents, substantial development has been achieved toward practical and selective amination protocols. Notably, Du Bois's group developed the dirhodium(II,II) carboxylate catalytic system for direct C(sp)-H amidations via Rh-sulfonyl nitrene intermediates. Read More

Acc Chem Res 2022 Aug 13;55(15):2138-2147. Epub 2022 Jul 13.

Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States.

ConspectusCyclometalated π-allyliridium-,-benzoate complexes discovered in the Krische laboratory display unique amphiphilic properties, catalyzing both nucleophilic carbonyl allylation and electrophilic allylation of diverse amines as well as nitronates. Given the importance of chiral amines in FDA-approved small-molecule drugs, a collaboration with medicinal chemists at Genentech that included on-site graduate student internships was undertaken to explore and expand the scope of π-allyliridium-,-benzoate-catalyzed allylic amination and related processes. As described in this Account, our collective experimental studies have unlocked asymmetric allylic aminations of exceptionally broad utility and scope. Read More

Chem Sci 2022 May 14;13(19):5726-5733. Epub 2022 Apr 14.

Organic and Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology 4 Raja S. C. Mullick Road, Jadavpur Kolkata-700032 West Bengal India

We present here a copper-catalyzed electrophilic C-H amination of protected naphthylamines with -(benzoyloxy)amines, cyclization with the pendant amide, and carbon to nitrogen 1,2-directing group migration cascade to access ,-disubstituted 2-benzimidazolinones. Remarkably, this highly atom-economic tandem reaction proceeds through a C-H and C-C bond cleavage and three new C-N bond formations in a single operation. Intriguingly, the reaction cascade was altered by the subtle tuning of the directing group from picolinamide to thiopicolinamide furnishing 2-heteroaryl-imidazoles the extrusion of hydrogen sulfide. Read More

Angew Chem Int Ed Engl 2022 08 13;61(31):e202205159. Epub 2022 Jun 13.

Hubei Engineering Research Center for Biomaterials and Medical Protective Materials, Hubei Key Laboratory of Bioinorganic Chemistry & Materia Medica, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology (HUST), Luoyu Road 1037, Wuhan, 430074, China.

Reported here is the first catalytic atroposelective electrophilic amination of indoles, which delivers functionalized atropochiral N-sulfonyl-3-arylaminoindoles with excellent optical purity. This reaction was furnished by 1,6-nucleophilic addition to p-quinone diimines. Control experiments suggest an ionic mechanism that differs from the radical addition pathway commonly proposed for 1,6-addition to quinones. Read More